To Explain the World: The Discovery of Modern Science Read Free Page A

Neoplatonism, partly through the example of Saint Augustine. Aristotle’s writings were naturalistic in a way that Plato’s were not, and his vision of a cosmos governed by laws, even laws as ill-developed as his were, presented an image of God’s hands in chains, the same image that had so disturbed al-Ghazali. The conflict over Aristotle was at least in part a conflict between two new mendicant orders: the Franciscans, or gray friars, founded in 1209, who opposed the teaching of Aristotle; and the Dominicans, or black friars, founded around 1216, who embraced “The Philosopher.”
    This conflict was chiefly carried out in new European institutions of higher learning, the universities. One of the cathedral schools, at Paris, received a royal charter as a university in 1200. (There was a slightly older university at Bologna, but it specialized in law and medicine, and did not play an important role in medieval physical science.) Almost immediately, in 1210, scholars at the University of Paris were forbidden to teach the books of Aristotle on natural philosophy. Pope Gregory IX in 1231 called for Aristotle’s works to be expurgated, so that the useful parts could be safely taught.
    The ban on Aristotle was not universal. His works were taught at the University of Toulouse from its founding in 1229. At Paris the total ban on Aristotle was lifted in 1234, and in subsequent decades the study of Aristotle became the center of education there. This was largely the work of two thirteenth-century clerics: Albertus Magnus and Thomas Aquinas. In the fashion of the times, they were given grand doctoral titles: Albertus was the “Universal Doctor,” and Thomas the “Angelic Doctor.”
    Albertus Magnus studied in Padua and Cologne, became a Dominican friar, and in 1241 went to Paris, where from 1245 to 1248 he occupied a professorial chair for foreign savants. Later he moved to Cologne, where he founded its university. Albertus was a moderate Aristotelian who favored the Ptolemaic system over Aristotle’s homocentric spheres but was concerned about its conflict with Aristotle’s physics. He speculated that the Milky Way consists of many stars and (contrary to Aristotle) that the markings on the Moon are intrinsic imperfections. The example of Albertus was followed a little later by another German Dominican, Dietrich of Freiburg, who independently duplicated some of al-Farisi’s work on the rainbow. In 1941 the Vatican declared Albertus the patron saint of all scientists.
    Thomas Aquinas was born a member of the minor nobility of southern Italy. After his education at the monastery of Monte Cassino and the University of Naples, he disappointed his family’s hopes that he would become the abbot of a rich monastery; instead, like Albertus Magnus, he became a Dominican friar. Thomas went to Paris and Cologne, where he studied under Albertus. He then returned to Paris, and served as professor at the university in 1256–1259 and 1269–1272.
    The great work of Aquinas was the Summa Theologica , a comprehensive fusion of Aristotelian philosophy and Christian theology. In it, he took a middle ground between extreme Aristotelians, known as Averroists after Ibn Rushd; and the extreme anti-Aristotelians, such as members of the newly founded Augustinian order of friars. Aquinas strenuously opposed a doctrine that was widely (but probably unjustly) attributed to thirteenth-century Averroists like Siger of Brabant and Boethius of Dacia. According to this doctrine, it is possible to hold opinions true in philosophy, such as the eternity of matter or the impossibility of the resurrection of the dead, while acknowledging that they are false in religion. For Aquinas, there could be only one truth. In astronomy, Aquinas leaned toward Aristotle’s homocentric theory of the planets, arguing that this theory was founded on reason while Ptolemaic theory merely agreed withobservation, and another hypothesis might also fit the data. On the other